[Don W]

THIS guy has a far more plausible explanation for ice ages and extinctions than any other theoretician I've yet found.

[planetesimal]

Thanks for the link, but that site design is so mid-nineties it merits only a quick glance, and a quick and fruitless search for, e.g., the word 'methane' confirms the wisdom of moving on.

I can't think of a single person, let alone scientist, who denies that glaciation occurs in cycles governed by solar and planetary factors. I can think of somebody who aims to profit directly from a dubious collation of information. The guy flogging that book.